Appearances can so often be deceptive. As Nairo Quintana sat impassively in the dwindling leading group on the stiff climb out of La Zubia on stage 6 of the Vuelta a España, he seemed the most comfortable of the general classification contenders.

As his Movistar stable-mate Alejandro Valverde forced the pace at the front of that group through the stiffest section of the short but inexorably steep climb, it seemed as though he was sacrificing his own ambitions to set up Quintana.

Instead, however, it was Valverde himself who sprinted to stage victory and reclaimed the red jersey at the summit, while Quintana allowed a fissure to open before him when the group fragmented in the final 500 metres.

The Colombian managed to limit the damage sufficiently to cross the line in 5th place, but he conceded 12 seconds – and time bonuses – to Valverde and danger men Chris Froome (Sky) and Alberto Contador (Tinkoff-Saxo).

Quintana now lies second overall, 15 seconds down on Valverde, and while he remains just ahead of Contador (third at 18 seconds) and Froome (fourth at 22 seconds), he has handed back much of the gains he made in Saturday's opening team time trial.

Speaking in Ronda on the eve of this stage, Quintana had sounded a decidedly cautious note when he wondered if the short, sharp climb above La Zubia was arriving too early in the race for his liking, and that cagey prognosis was borne out in the closing kilometre.

On crossing the finish line, Quintana was immediately engulfed by a group of reporters, and after leaning over his handlebars to compose himself, he looked to put those frantic closing metres in the context of the entire three weeks. In particular, he said that the extreme heat in Andalusia had exacted its toll on the Alto Cumbres Verdes.

"Valverde did great work, but unfortunately the sun affected me quite a bit and I didn't finish as I would have liked," Quintana said. "But I didn't lose too much time and I'm not going to give it too much importance."

Quintana struggled with illness through the opening half of May's Giro d'Italia only to turn the race on its head on the controversial, snowbound tappone to Val Martello, and he will hope for a similar upturn in Spain.

Although Quintana won the Vuelta a Burgos earlier this month, he said that he was still missing sharpness after spending over two months training at home in Colombia after the Giro. "I'm still lacking some rhythm, and you could see in the final kilometre that I'm still not in my top condition, but I hope to keep progressing in the coming stages."

In that light, it was perhaps counter-productive that Valverde was so insistent in his forcing on the imposing road to nowhere above La Zubia, but Quintana was careful to douse any suggestion that Movistar's front men weren't singing from the same song sheet.

"I'm extremely happy for Alejandro. He's a great rider. He did great work for me in the finale and was still able to win the stage, which is something not many riders can do," Quintana said. "The important thing for us is to keep the win within the team, no matter whether it's him or me, and for the time being, that goal is being fulfilled."